dragdrop-debug.js

这是YUI的源码及相关示例。里面有很多很炫的Javascript效果。

                YAHOO.log("getXY failed", "info", "DragDropMgr");
                return null;
            }

            x1 = pos[0];
            x2 = x1 + el.offsetWidth;
            y1 = pos[1];
            y2 = y1 + el.offsetHeight;

            t = y1 - oDD.padding[0];
            r = x2 + oDD.padding[1];
            b = y2 + oDD.padding[2];
            l = x1 - oDD.padding[3];

            return new YAHOO.util.Region( t, r, b, l );
        },

        /**
         * Checks the cursor location to see if it over the target
         * @method isOverTarget
         * @param {YAHOO.util.Point} pt The point to evaluate
         * @param {DragDrop} oTarget the DragDrop object we are inspecting
         * @param {boolean} intersect true if we are in intersect mode
         * @param {YAHOO.util.Region} pre-cached location of the dragged element
         * @return {boolean} true if the mouse is over the target
         * @private
         * @static
         */
        isOverTarget: function(pt, oTarget, intersect, curRegion) {
            // use cache if available
            var loc = this.locationCache[oTarget.id];
            if (!loc || !this.useCache) {
                YAHOO.log("cache not populated", "info", "DragDropMgr");
                loc = this.getLocation(oTarget);
                this.locationCache[oTarget.id] = loc;

                YAHOO.log("cache: " + loc, "info", "DragDropMgr");
            }

            if (!loc) {
                YAHOO.log("could not get the location of the element", "info", "DragDropMgr");
                return false;
            }

            //YAHOO.log("loc: " + loc + ", pt: " + pt);
            oTarget.cursorIsOver = loc.contains( pt );

            // DragDrop is using this as a sanity check for the initial mousedown
            // in this case we are done.  In POINT mode, if the drag obj has no
            // contraints, we are done. Otherwise we need to evaluate the 
            // region the target as occupies to determine if the dragged element
            // overlaps with it.
            
            var dc = this.dragCurrent;
            if (!dc || (!intersect && !dc.constrainX && !dc.constrainY)) {

                //if (oTarget.cursorIsOver) {
                    //YAHOO.log("over " + oTarget + ", " + loc + ", " + pt, "warn");
                //}
                return oTarget.cursorIsOver;
            }

            oTarget.overlap = null;


            // Get the current location of the drag element, this is the
            // location of the mouse event less the delta that represents
            // where the original mousedown happened on the element.  We
            // need to consider constraints and ticks as well.

            if (!curRegion) {
                var pos = dc.getTargetCoord(pt.x, pt.y);
                var el = dc.getDragEl();
                curRegion = new YAHOO.util.Region( pos.y, 
                                                   pos.x + el.offsetWidth,
                                                   pos.y + el.offsetHeight, 
                                                   pos.x );
            }

            var overlap = curRegion.intersect(loc);

            if (overlap) {
                oTarget.overlap = overlap;
                return (intersect) ? true : oTarget.cursorIsOver;
            } else {
                return false;
            }
        },

        /**
         * unload event handler
         * @method _onUnload
         * @private
         * @static
         */
        _onUnload: function(e, me) {
            this.unregAll();
        },

        /**
         * Cleans up the drag and drop events and objects.
         * @method unregAll
         * @private
         * @static
         */
        unregAll: function() {
            YAHOO.log("unregister all", "info", "DragDropMgr");

            if (this.dragCurrent) {
                this.stopDrag();
                this.dragCurrent = null;
            }

            this._execOnAll("unreg", []);

            //for (var i in this.elementCache) {
                //delete this.elementCache[i];
            //}
            //this.elementCache = {};

            this.ids = {};
        },

        /**
         * A cache of DOM elements
         * @property elementCache
         * @private
         * @static
         * @deprecated elements are not cached now
         */
        elementCache: {},
        
        /**
         * Get the wrapper for the DOM element specified
         * @method getElWrapper
         * @param {String} id the id of the element to get
         * @return {YAHOO.util.DDM.ElementWrapper} the wrapped element
         * @private
         * @deprecated This wrapper isn't that useful
         * @static
         */
        getElWrapper: function(id) {
            var oWrapper = this.elementCache[id];
            if (!oWrapper || !oWrapper.el) {
                oWrapper = this.elementCache[id] = 
                    new this.ElementWrapper(YAHOO.util.Dom.get(id));
            }
            return oWrapper;
        },

        /**
         * Returns the actual DOM element
         * @method getElement
         * @param {String} id the id of the elment to get
         * @return {Object} The element
         * @deprecated use YAHOO.util.Dom.get instead
         * @static
         */
        getElement: function(id) {
            return YAHOO.util.Dom.get(id);
        },
        
        /**
         * Returns the style property for the DOM element (i.e., 
         * document.getElById(id).style)
         * @method getCss
         * @param {String} id the id of the elment to get
         * @return {Object} The style property of the element
         * @deprecated use YAHOO.util.Dom instead
         * @static
         */
        getCss: function(id) {
            var el = YAHOO.util.Dom.get(id);
            return (el) ? el.style : null;
        },

        /**
         * Inner class for cached elements
         * @class DragDropMgr.ElementWrapper
         * @for DragDropMgr
         * @private
         * @deprecated
         */
        ElementWrapper: function(el) {
                /**
                 * The element
                 * @property el
                 */
                this.el = el || null;
                /**
                 * The element id
                 * @property id
                 */
                this.id = this.el && el.id;
                /**
                 * A reference to the style property
                 * @property css
                 */
                this.css = this.el && el.style;
            },

        /**
         * Returns the X position of an html element
         * @method getPosX
         * @param el the element for which to get the position
         * @return {int} the X coordinate
         * @for DragDropMgr
         * @deprecated use YAHOO.util.Dom.getX instead
         * @static
         */
        getPosX: function(el) {
            return YAHOO.util.Dom.getX(el);
        },

        /**
         * Returns the Y position of an html element
         * @method getPosY
         * @param el the element for which to get the position
         * @return {int} the Y coordinate
         * @deprecated use YAHOO.util.Dom.getY instead
         * @static
         */
        getPosY: function(el) {
            return YAHOO.util.Dom.getY(el); 
        },

        /**
         * Swap two nodes.  In IE, we use the native method, for others we 
         * emulate the IE behavior
         * @method swapNode
         * @param n1 the first node to swap
         * @param n2 the other node to swap
         * @static
         */
        swapNode: function(n1, n2) {
            if (n1.swapNode) {
                n1.swapNode(n2);
            } else {
                var p = n2.parentNode;
                var s = n2.nextSibling;

                if (s == n1) {
                    p.insertBefore(n1, n2);
                } else if (n2 == n1.nextSibling) {
                    p.insertBefore(n2, n1);
                } else {
                    n1.parentNode.replaceChild(n2, n1);
                    p.insertBefore(n1, s);
                }
            }
        },

        /**
         * Returns the current scroll position
         * @method getScroll
         * @private
         * @static
         */
        getScroll: function () {
            var t, l, dde=document.documentElement, db=document.body;
            if (dde && (dde.scrollTop || dde.scrollLeft)) {
                t = dde.scrollTop;
                l = dde.scrollLeft;
            } else if (db) {
                t = db.scrollTop;
                l = db.scrollLeft;
            } else {
                YAHOO.log("could not get scroll property", "info", "DragDropMgr");
            }
            return { top: t, left: l };
        },

        /**
         * Returns the specified element style property
         * @method getStyle
         * @param {HTMLElement} el          the element
         * @param {string}      styleProp   the style property
         * @return {string} The value of the style property
         * @deprecated use YAHOO.util.Dom.getStyle
         * @static
         */
        getStyle: function(el, styleProp) {
            return YAHOO.util.Dom.getStyle(el, styleProp);
        },

        /**
         * Gets the scrollTop
         * @method getScrollTop
         * @return {int} the document's scrollTop
         * @static
         */
        getScrollTop: function () { return this.getScroll().top; },

        /**
         * Gets the scrollLeft
         * @method getScrollLeft
         * @return {int} the document's scrollTop
         * @static
         */
        getScrollLeft: function () { return this.getScroll().left; },

        /**
         * Sets the x/y position of an element to the location of the
         * target element.
         * @method moveToEl
         * @param {HTMLElement} moveEl      The element to move
         * @param {HTMLElement} targetEl    The position reference element
         * @static
         */
        moveToEl: function (moveEl, targetEl) {
            var aCoord = YAHOO.util.Dom.getXY(targetEl);
            YAHOO.log("moveToEl: " + aCoord, "info", "DragDropMgr");
            YAHOO.util.Dom.setXY(moveEl, aCoord);
        },

        /**
         * Gets the client height
         * @method getClientHeight
         * @return {int} client height in px
         * @deprecated use YAHOO.util.Dom.getViewportHeight instead
         * @static
         */
        getClientHeight: function() {
            return YAHOO.util.Dom.getViewportHeight();
        },

        /**
         * Gets the client width
         * @method getClientWidth
         * @return {int} client width in px
         * @deprecated use YAHOO.util.Dom.getViewportWidth instead
         * @static
         */
        getClientWidth: function() {
            return YAHOO.util.Dom.getViewportWidth();
        },

        /**
         * Numeric array sort function
         * @method numericSort
         * @static
         */
        numericSort: function(a, b) { return (a - b); },

        /**
         * Internal counter
         * @property _timeoutCount
         * @private
         * @static
         */
        _timeoutCount: 0,

        /**
         * Trying to make the load order less important.  Without this we get
         * an error if this file is loaded before the Event Utility.
         * @method _addListeners
         * @private
         * @static
         */
        _addListeners: function() {
            var DDM = YAHOO.util.DDM;
            if ( YAHOO.util.Event && document ) {
                DDM._onLoad();
            } else {
                if (DDM._timeoutCount > 2000) {
                    YAHOO.log("DragDrop requires the Event Utility", "error", "DragDropMgr");
                } else {
                    setTimeout(DDM._addListeners, 10);
                    if (document && document.body) {
                        DDM._timeoutCount += 1;
                    }
                }
            }
        },

        /**
         * Recursively searches the immediate parent and all child nodes for 
         * the handle element in order to determine wheter or not it was 
         * clicked.
         * @method handleWasClicked
         * @param node the html element to inspect
         * @static
         */
        handleWasClicked: function(node, id) {
            if (this.isHandle(id, node.id)) {
                YAHOO.log("clicked node is a handle", "info", "DragDropMgr");
                return true;
            } else {
                // check to see if this is a text node child of the one we want
                var p = node.parentNode;
                // YAHOO.log("p: " + p);